JPH06101107B2 - Tracking control device for magnetic recording / reproducing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tracking control device used in a multi-track magnetic recording / reproducing device using a magnetic tape as a recording medium, and particularly to a high-speed tracking device with a narrow track width, The present invention relates to a tracking control device of a magnetic recording / reproducing device that performs high-density and large-capacity recording / reproducing.

[Conventional technology]

Conventionally, a magnetic recording / reproducing apparatus used as an audio apparatus usually has a configuration in which the number of tracks and the number of heads are equal to each other, except for those having a rotary head. The above-mentioned number of tracks refers to the total number of data tracks formed in parallel to the tape running direction, and the number of heads refers to the number of heads in a combination head that integrally has a magnetic head such as a recording head, a reproducing head or a recording / reproducing head. Refers to the number of magnetic heads, and so on. The magnetic recording / reproducing apparatus as described above is provided with a tape / head relative position regulating means for regulating the relative position of the magnetic tape and the magnetic head, and is constituted by a pair of flanges for guiding the upper and lower ends of the magnetic tape. It is most common to provide a guide post or the like having a groove formed on the tape running path.

On the other hand, in a multi-track magnetic recording / reproducing apparatus which is a backup storage device of an information processing system and is generally called a cassette streamer, a recording method called a serpentine method in which the number of heads is smaller than the number of recording tracks is adopted. ing. The serpentine system has at least two sets of recording and reproducing heads, one for the forward direction and the other for the backward direction of the tape running direction, and each recording and reproducing head can correspond to a plurality of tracks. When information is recorded on the tape, the magnetic tape is not recorded simultaneously on a plurality of tracks, but the magnetic tape is run in the forward direction and the reverse direction to sequentially record one track at a time. During this operation, the tracks are switched by moving the two sets of magnetic heads in the tape width direction, and the magnetic heads are positioned at desired track positions. As the head / tape relative position regulating means, for example, as disclosed in Japanese Patent Laid-Open No. 62-183019, in addition to the regulation by the flanges described above, a head positioning technique by open loop control by a stepping motor is known. Has been.

Further, in recent years, with the development of thin-film magnetic heads, combination heads having a large number of heads have been developed, and the multi-track magnetic recording / reproducing apparatus can have higher density. With such a device, recording with a narrow track width can be performed, and the allowable off-track amount is also small.
Therefore, as the tape / head relative position restricting means, in addition to the restricting structure by the above-mentioned flange, a relative position detecting means between the magnetic head and the magnetic tape or track, and a head driving means for moving the magnetic head in the tape width direction. Accordingly, a configuration is adopted in which the magnetic head is controlled following the waving of the magnetic tape.

An example of such a device is a fixed head digital audio tape recorder having the same number of heads and tracks. In the same device, as disclosed in, for example, the Technical Report EA83-56, the Technical Report EA81-64, and the Sharp Technical Report 1984-28, the servo-dedicated track recorded on the magnetic tape is moved in the tape width direction. The two reproducing heads arranged side by side are traced, the reproduction outputs thereof are compared, and follow-up control is performed, whereby the relative position between the magnetic head and the magnetic tape is regulated.

As another example of the tape head relative position regulating means, in a magnetic recording / reproducing apparatus in which the number of heads and the number of tracks are equal, there is a configuration for optically or magnetically detecting the relative position between the magnetic tape end and the magnetic head. , Shokoku Sho 63-6481
It is disclosed in Japanese Patent No.

[Problems to be Solved by the Invention]

However, in the tape / head relative position regulating means by the guide post having the flange, the upper and lower ends of the magnetic tape are brought into contact with the flange of the guide post to prevent the vertical movement of the magnetic tape. When a magnetic tape having a width wider than the distance travels, mechanical stress is applied to the upper and lower ends of the magnetic tape, which may damage the upper and lower ends. Therefore, in the above-mentioned regulation means, the regulation width of several tens of μm is the limit because damage to the end of the magnetic tape must be avoided. Therefore, in a high-density magnetic recording / reproducing apparatus having an allowable off-track amount of about several tens to several tens of μm, it is not sufficient to limit the fluctuation of the magnetic tape by the above flanges.

Next, in a conventional multi-track magnetic recording / reproducing apparatus such as a fixed head digital audio tape recorder, the track pitch is about several hundred μm. Therefore, by adopting a thin film head, recording and recording corresponding to a plurality of tracks of the magnetic tape can be performed. It was possible to construct a combination head with an integrated reproducing head.

However, in the case of further increasing the recording density, it is possible to narrow the track width by narrowing the gap width of the magnetic head, but there is a limit to the integration of the thin film head, so the track pitch is set to a certain level or more. It cannot be made smaller. In addition, increasing the number of heads leads to an increase in the circuit scale, resulting in an increase in cost. Therefore, it is difficult to achieve a high-density magnetic recording / reproducing apparatus having a track pitch of several tens of μm and a number of tracks of several tens to several hundreds with a configuration in which the number of heads and the number of tracks are equal.

Next, in a multi-track magnetic recording / reproducing apparatus such as that found in a serpentine type cassette streamer, a small number of magnetic heads are moved in the tape width direction to perform recording / reproducing on a large number of tracks. Even if the number of tracks increases, it is possible to deal with it by moving the magnetic head many times. Therefore, there is no obstacle to the integration of the thin film head.

However, for example, when the track pitch is tens of μm, the track width is naturally tens of μm, and the allowable off-track amount is tens to several μm. In this case, the tape head relative position regulation means based on the regulation by the flanges and the stepping motor open loop control cannot cope with the above allowable off-track amount.

Therefore, it is conceivable to perform the feedback control by the relative position sensor between the magnetic head and the magnetic tape and the head drive means to perform the tracking control to solve the above-mentioned problem of the allowable off-track amount.

However, in a configuration having a large number of tracks and a small number of heads, movement of several hundreds of μm to several mm is required during the track switching operation, and tracking control requires a relative position sensor having a resolution of several μm. Therefore, the feedback servo by the tape edge detection as used in the fixed head digital audio tape recorder described above requires a dynamic range of the sensor of about 60 dB, which is difficult to realize in terms of cost and accuracy. Also, in order to perform tracking control by the servo track,
In addition to the need for a large number of servo tracks, recording on the servo tracks poses a problem, and even with this method, higher density recording cannot be supported.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, a tracking controller for a magnetic recording / reproducing apparatus according to a first aspect of the present invention includes a combination head having a number of magnetic heads smaller than the number of tracks of a magnetic tape, and the combination head. A head drive means for moving the plurality of tracks in the width direction of the magnetic tape formed in parallel to the tape running direction, and by a plurality of track switching operations by moving the combination head by the head drive means, In a magnetic recording / reproducing apparatus for performing recording or reproduction on all tracks, the combination head has a number of light-receiving elements equal to the number of tracks of a magnetic tape corresponding to a predetermined magnetic head of the combination head in the tape width direction. Are provided on one end side and the other end side of The light-receiving elements of the end side light-receiving element group and the light-receiving elements of the other end-side light-receiving element group have individual correspondences and are arranged side by side in the tape width direction. The light receiving element of the one end side light receiving element group and the other end side light receiving element group having a correspondence relationship with a predetermined track of the tape, when the magnetic head moves to an arbitrary track position, Outputs of a pair of light receiving elements corresponding to this track are provided so as to have a constant relationship with each other, and a light emitting means is provided at a position facing the light receiving elements through both ends in the width direction of the magnetic tape. The driving means, when the magnetic head of the combination head is moved to a predetermined track position, receives a pair of received light corresponding to the predetermined track by the incident light from the light emitting means through both ends in the tape width direction. Elementary As each other output satisfies a predetermined relationship, and characterized in that performing feedback control.

In order to solve the above-mentioned problems, a tracking control device for a magnetic recording / reproducing device according to a second aspect of the present invention includes a combination head having a number of magnetic heads smaller than the number of tracks of a magnetic tape, and the combination head. A head drive means for moving the plurality of tracks in the width direction of the magnetic tape formed in parallel to the tape running direction, and by a plurality of track switching operations by moving the combination head by the head drive means, In a magnetic recording / reproducing apparatus for performing recording or reproduction on all tracks, a slit plate is integrally provided on the combination head, and a slit of a magnetic tape corresponding to a predetermined magnetic head of the combination head is provided on the slit plate. There are as many windows as there are tracks in the tape width direction. Is formed on one end portion side and the other end side,
On the side opposite to the magnetic tape side of the slit plate, the light receiving elements individually corresponding to each of the above windows are fixed separately from the combination head, and the window and the other end of the one end side window group in the slit plate are fixed. The windows of the group side window group are arranged in parallel in the tape width direction so as to have a corresponding relationship with each other, and each of the corresponding pair of windows has a corresponding relationship with a predetermined track of the magnetic tape, and The window of the one end side window group and the window of the other end side window group are provided through a pair of windows corresponding to the track and both end sides in the tape width direction when the magnetic head moves to an arbitrary track position. Are provided so that the outputs of the light receiving elements due to the incident light have a constant relationship, and a light emitting means is provided at a position facing the light receiving elements via both end sides in the width direction of the magnetic tape and the slit plates, The head drive means is a combination When the magnetic head of the magnetic head is moved to a predetermined track position, incident light from the light emitting means through the pair of windows corresponding to the predetermined track and both end portions in the tape width direction causes both windows to move. So that the outputs of the corresponding light receiving elements satisfy a certain relationship,
The feature is that feedback control is performed.

[Action]

According to the structure of claim 1, for example, when reproducing a predetermined track of the magnetic tape, the combination driving head drives the combination head, and the predetermined magnetic head of the combination head drives the predetermined track of the magnetic tape. Move to position. Along with this, the plurality of light receiving elements provided integrally with the combination head also move at the same time.
Due to this movement, the outputs of the pair of light receiving elements of the one end side light receiving element group and the other end side light receiving element group corresponding to the predetermined track are received by the light receiving surface being blocked by the widthwise end portions of the magnetic tape. The amount changes.

Here, the light receiving elements of the one end side light receiving element group and the light receiving elements of the other end side light receiving element group respectively have a corresponding relationship,
Each pair of corresponding light receiving elements has a correspondence relationship with a predetermined track of the magnetic tape. Further, the light receiving element of the one end side light receiving element group and the light receiving element of the other end side light receiving element group are the outputs of the pair of light receiving elements corresponding to this track when the magnetic head moves to an arbitrary track position. Are provided so as to have a certain relationship. Therefore, the head drive means, when the magnetic head of the combination head is moved to a predetermined track position, by the incident light from the light emitting means via both end sides in the width direction of the magnetic tape,
Feedback control is performed so that the outputs of the pair of light receiving elements corresponding to the predetermined track satisfy a certain relationship. As a result, the relative position between the magnetic head and the track is tracked and controlled, and the relative positions of the two are held at accurate positions.

With the above-mentioned configuration, it is possible to perform the track following control of about several μm and the track switching operation of several hundred μm to several mm by one head driving means, and the track pitch is several tens μm and the number of tracks. It is possible to realize high-accuracy and large-capacity magnetic recording / reproducing with a value of several tens to several hundreds.

It should be noted that the positioning accuracy of each light receiving element does not cause any problem if these light receiving elements are manufactured by semiconductor technology, and a highly accurate position sensor can be obtained.

According to the structure of claim 2, when the predetermined track of the magnetic tape is reproduced, when the combination head is driven and the predetermined magnetic head moves to the predetermined track position, the combination of the combination head and the combination head is integrated. The slit plate provided on the table also moves at the same time. By this movement, the plurality of windows formed in the slit plate also move, and through the pair of windows of the one end side window group and the other end side window group corresponding to the predetermined track, the light receiving corresponding to these windows is received. Light is incident on the element.

Here, the windows of the one end side window group and the windows of the other end side window group respectively have a correspondence relationship, and each corresponding pair of windows has a correspondence relationship with a predetermined track of the magnetic tape. There is. Further, the window of the one end side window group and the window of the other end side window group are, when the magnetic head moves to an arbitrary track position, a pair of windows corresponding to the track and both end sides in the tape width direction. The outputs of the light receiving elements due to the light incident through the light source are provided so as to have a constant relationship. Therefore, when the magnetic head of the combination head is moved to a predetermined track position, the head driving means emits light from the light emitting means through the pair of windows corresponding to the predetermined track and both end sides in the tape width direction. Feedback control is performed by the incident light so that the outputs of the light receiving elements corresponding to the both windows described above satisfy a certain relationship. As a result, the relative position between the magnetic head and the track is tracked and controlled, and the relative positions of the two are held at accurate positions.

With the above-mentioned configuration, it is possible to realize high-accuracy and large-capacity magnetic recording / reproducing similar to the magnetic recording / reproducing apparatus described above.

It should be noted that the positioning accuracy of the plurality of windows in the slit plate does not cause any problem if these windows are produced by an etching technique, and a highly accurate position sensor can be obtained.

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

This magnetic recording / reproducing apparatus is of the serpentine type in which recording / reproducing is performed with a smaller number of magnetic heads than the number of tracks on the magnetic tape. First, the outline of the system will be described with reference to FIG. In the figure, the running direction of the magnetic tape 21 is X, and the width direction of the magnetic tape 21 is Y. A track group 22 is formed on the magnetic tape 21, and the track group 22 has 16 tracks T _{1 to} R ₁₆ at an equal pitch a in the Y direction. For the track group 22 described above, a combination head 23 including _four recording heads W _{1 to} W ₄ and reproducing heads R _{1 to} R ₄ that are integrated is arranged. The recording heads W _{1 to} W ₄ are arranged in parallel in the Y direction at equal pitches b (b = 4a), and the reproducing heads R _{1 to} R ₄ correspond to the corresponding recording heads W ₁
~ W ₄ and are arranged in parallel in the X direction or the -X direction. These paired recording heads W _{1 to} W ₄ and reproducing head R ₁
To R ₄ each other in a state in which interchanged for each arrangement position of the Y-direction,
They are arranged alternately.

In the recording or reproducing operation, the combination head 23 is first driven to the position shown in FIG. That is,
The centers of the recording head W ₁ and the reproducing head R ₁ coincide with the center of the track T ₁ , and similarly, the centers of the recording head W ₂ , the reproducing head R ₂ and the track T _5, and the recording head W ₃ and the reproducing head R ₃ And the center of track T ₉ and recording head W ₄ and playback head R ₄
And the center of the track T ₁₃ are coincident with each other. Next, while recording this relative position, in the case of recording, the magnetic tape 21 is run in the X direction, and the tracks T ₁ and T ₉ are simultaneously recorded by the recording heads W ₁ and W ₃ . When the recording up to the tape end is completed, the magnetic tape 21 is moved in the -X direction this time, and the tracks T ₅ and T ₁₃ are simultaneously recorded by the recording heads W ₂ and W ₄ . After the completion of recording to the tape end, is moved by a the combination head 23 in the -Y direction, the center of the recording head W ₁ and the reproducing head R ₁ is distribution to coincide with the center of the track T _2. While maintaining this relative position, the magnetic tape 21 is made to run again in the X direction, and the recording heads W ₁ and W _{3 are used to} track.
Record at T ₂ and T ₁₀ . When the recording up to the tape end is completed, the magnetic tape 21 is moved in the −X direction this time, and the recording heads W ₂ and W ₄ are used to track T ₆ and T.
Record to ₁₄ . Similarly, for all tracks T ₁
Record to ~ T ₁₆ . In the above example, since the number of reproducing heads and recording heads is 4 for 16 tracks, the relative position between the magnetic tape 21 and the combination head 23 is 4 positions.

Next, the tracking control device of the magnetic recording / reproducing apparatus of the present invention will be described with reference to FIGS. 1 and 2.

The magnetic recording / reproducing apparatus is shown in FIGS. 1 and 2 (a) (b).
As shown in, a combination head 3 for recording / reproducing on / from the magnetic tape 1 is provided, and the combination head 3 is integrally provided with a light receiving element holding member 4.

As shown in FIG. 1, the magnetic tape 1 has a track group 2 composed of ₄₈ tracks T _{1 to} T ₄₈ formed at equal pitches in the Y direction. In this embodiment, the width C of the magnetic tape 1 is set to 1/4 inch and the track pitch is set to 120 μm. The waving of this magnetic tape 1 is
It is suppressed to ± 50 μm by flanges (not shown) that regulate the ends of the magnetic tape 1 in the ± Y direction.

Combination head 3 is provided with respective eight recording heads W ₁ to _W-8 and the reproducing head R ₁ to R ₈ which forms an integral. Each of the recording heads W _{1 to} W ₈ has a Y pitch of 720 μm.
The reproducing heads R _{1 to} R ₈ are arranged side by side in the X direction or the −X direction in pairs with the corresponding recording heads W _{1 to} W ₈ . The recording heads W _{1 to} W ₈ and the reproducing heads R _{1 to} R ₈ forming the pair are alternately arranged in a state in which they are interchanged at each arrangement position in the Y direction. In such a combination head 3, when the magnetic tape 1 is running in the X direction, recording is performed by the four recording heads W ₁ , W ₃ , W ₅ , W ₇ , and the magnetic tape 1 is moved in the −X direction. It is configured such that recording is performed by _four recording heads W ₂ , W ₄ , W _6, and W ₈ when the recording head is traveling to. Furthermore, each time the magnetic tape 1 reciprocates, the combination head 3 is driven in the -Y direction and takes six relative positions with respect to the magnetic tape 1, so that all 48 tracks T _{1 to} T ₄₈ are recorded. Recording and reproduction of can be performed. Further, in the light receiving element holding member 4, a light receiving element group 5 as one end side light receiving element group consisting of _six light receiving elements Da _{1 to} Da 6 is provided at a portion corresponding to the vicinity of the + Y direction end portion of the magnetic tape 1. provided, at a portion corresponding to the vicinity of the -Y direction end portion, likewise, the light receiving element group 6 is provided as the other end side light receiving element group of six light receiving element Db ₁ Db _6. The number of six light receiving elements of these light receiving element groups 5 and 6 corresponds to the number of tracks T _{1 to} T ₆ within a range in which, for example, the pair of recording head W ₁ and reproducing head R ₁ of the combination head 3 can move. ing. The light receiving elements Da _{1 to} Da ₆ and Db _{1 to} Db ₆ have the same output level per unit light receiving area, and since the light receiving element holding member 4 is provided integrally with the combination head 3, It moves along with the movement in the ± Y direction. The light-receiving surfaces of the light-receiving elements Da _{1 to} Da ₆ and Db _{1 to} Db ₆ are each formed to have a width e in the Y direction which corresponds to the waving of the magnetic tape 1, and a width in the X direction to obtain a sufficient output. The width f is set to a suitable width. In the present embodiment, the width e is set to 100 μm. Light receiving element Da _{1 to} Da ₆
In Db _{1 to} Db ₆ , the light receiving elements Da ₁ and Db ₁ are provided on the −Y direction end side, and the light receiving elements Da _{2 to} Da ₆ and Db _{2 to} Db ₆ are connected to the magnetic tape 1.
They are arranged in a row in the + Y direction at the same pitch d (d = 120 μm) as the track pitch. In addition, the light receiving element Da
₁ and the light-receiving element Db ₁ are arranged at a position shifted in the Y direction by 1/4 inch of the width of the magnetic tape 1, and the combination head 3, for example, the recording head W ₁ and the reproducing head R ₁ are located at the track T ₁ position. At some point, the centers of the light receiving elements Da ₁ and Db ₁ are arranged at positions that coincide with the edge portions of the magnetic tape 1 in the ± Y directions.

The light receiving elements Da _{1 to} Da ₆ and Db _{1 to} Db ₆ are connected to a head driving means (not shown). The head drive means receives the light-receiving elements Da _{1 to} Da ₆ when the combination head 3 is moved to the relative positions of the recording heads W _{1 to} W ₈ and the reproducing heads R _{1 to} R ₈ and the tracks T _{1 to} T _48. And the light receiving elements Db _{1 to} Db ₆ respectively, the combination head 3 is driven in the ± Y direction of the magnetic tape 1 by feedback control so that the output difference between the corresponding light receiving elements becomes zero, and the combination with the magnetic tape 1 is performed. The relative position with respect to the head 3 is held at a predetermined fixed position.

Further, as shown in FIG. 2 (a), the portions of the magnetic tape 1 facing the light receiving element groups 5 and 6 via the ± Y direction end portions respectively receive a sufficient amount of light. Element group 5
A light emitting means 8.8 capable of irradiating in six directions is provided.

In the above configuration, for example, in reproducing operation of the magnetic recording / reproducing apparatus, when reproducing all the tracks T _{1 to} T ₄₈ including the tracks T ₁ , T ₁₃ , T ₂₅ , T ₃₇ , the combination head 3 is Driven by the head driving means, the reproducing head R ₁ and the track T ₁ , the reproducing head R ₃ and the track T ₁₃ ,
Playhead R ₅ and track T ₂₅ , Playhead R ₇ and track T
₃₇ and ₃₇ move to relative positions with respect to the corresponding magnetic tape 1. At this time, the head driving means moves the combination head 3 by feedback control so that the difference between the output of the light receiving element Da _{1 and} the output of the light receiving element Db ₁ becomes zero, and also the waving of the magnetic tape 1 uses the combination head. 3, the combination head 3 is driven so that the relative position between the magnetic tape 1 and the combination head 3 is kept constant. Therefore, the relative position between the combination head 3 and the magnetic tape 1 is maintained at an accurate position. In this state, when the magnetic tape 1 is run in the X direction, the reproducing heads R ₁ , R ₃ , R ₅ , R ₇
Playback of tracks T ₁ , T ₁₃ , T _25, and T ₃₇ is performed.
When the reproduction up to the end of the magnetic tape 1 is completed, the magnetic tape 1 is moved in the -X direction this time, and the reproducing head R ₂
· The R ₄ · R ₆ · R ₈ track playback _{T 7 · T 19 · T 31} · T 43 is performed.

When the reproduction of one round trip is completed in this way, the combination head 3 is reproduced by the head driving means.
R ₁ and the track T ₂ , the reproducing head R ₃ and the track T ₁₄ , the reproducing head R ₅ and the track T ₂₆ , and the reproducing head R ₇ and the track T ₃₈ are moved to the relative positions of the corresponding magnetic tape 1.
At this time, the head driving means moves the combination head 3 by feedback control so that the difference between the output of the light receiving element Da ₂ and the output E of the light receiving element Db ₂ becomes zero. In this state, when the magnetic tape 1 is run in the X direction, the reproducing heads R ₁ , R ₃ , R _5, and R _{7 are used} to track T _2.
Playback of T ₁₄ , T _26, and T ₃₈ is performed. Thereafter, a track by the magnetic tape 1 in the -X direction _{T 8 · T 20 · T 32} · T 44
Is played.

Similarly, when reading tracks T ₃ , T ₁₅ , T ₂₇ , T ₃₉ and tracks T ₉ , T ₂₁ , T ₃₃ , T ₄₅ , the photodetector Da ₃ , Db ₃
Output difference, track T ₄ , T ₁₆ , T ₂₈ , T ₄₀ and track T
_During playback of ₁₀ / T ₂₂ / T ₃₄ / T ₄₆ , the output difference of the light receiving elements Da ₄ / Db ₄ , track T ₅ , T ₁₇ , T ₂₉ / T ₄₁ and track T ₁₁
・ During playback of T ₂₃ , T ₃₅ , T ₄₇ , the output difference of the light receiving elements Da ₅ , Db ₅ , track T ₆ , T ₁₈ , T ₃₀ , T ₄₂ and track T ₁₂ ,
When reproducing T ₂₄ , T _36, and T ₄₈ , the combination head 3 is moved after one round trip at each track position so that the output difference of the light receiving elements Da ₆ and Db ₆ becomes zero. switching operation and track follow-up operation is performed, the reproduction is completed for all the tracks T ₁ through T _48. The above operation is the same in the recording operation.

The output of a light receiving element such as a photodiode and a light emitting means such as a light emitting diode generally tend to vary due to the influence of ambient temperature. However, in the present tracking control device, the output difference between two predetermined light receiving elements is calculated and Since the configuration is such that the difference becomes zero, stable position control can be performed without being affected by temperature.

Second Embodiment Another embodiment of the present invention will be described below with reference to FIGS. 4 and 5. For convenience of explanation, members having the same functions as the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

The magnetic recording / reproducing apparatus is shown in FIGS. 4 and 5 (a) (b).
As shown in FIG. 3, a combination head 3 for recording / reproducing on / from the magnetic tape 1 is provided, and the combination head 3 is integrally provided with a slit plate 7. The configurations of the magnetic tape 1 and the combination head 3 are the same as those in the first embodiment. The waving of the magnetic tape 1 is suppressed to ± 50 μm by flanges (not shown) that regulate the ends of the magnetic tape 1 in the ± Y direction.

On the side of the slit plate 7 opposite to the magnetic tape 1 side, a light receiving element holding member 4 is fixedly provided separately from the combination head 3 and the slit plate 7.

The light-receiving element holding member 4 has six light-receiving elements Di at the portions corresponding to the ± Y direction ends of the magnetic tape 1, respectively.
Light receiving element groups 9 and 10 composed of _{1 to} Di ₆ and Dj _{1 to} Dj ₆ are provided. Photodetectors Di _{1 to} Di ₆ and Dj _{1 to} Dj ₆ are photodetectors Di ₁
-Dj ₁ is provided at the end of + X direction, and sequentially at pitch g-
They are arranged side by side in a row in the X direction, and the centers in the Y directions coincide with the edges of the magnetic tape 1 in the ± Y directions. These light receiving elements _{Di 1 ~Di 6 · Dj 1 ~Dj} 6 are independently a light passing through the ± each window in the Y-direction end side and below _{Si 1 ~Si 6 · Sj 1 ~Sj} 6 of the magnetic tape 1 individually And receive light. Light receiving element
The light receiving surfaces of Di _{1 to} Di ₆ and Dj _{1 to} Dj ₆ have the width l _{v in the} Y direction of the window Si ₁
~Si ₆ · Sj ₁ ~Sj wider than ₆ in the Y direction of the width e, the width l _H in the X direction is set to a narrow appropriate width than the pitch g. The light receiving elements Di _{1 to} Di ₆ and Dj _{1 to} Dj ₆ have the same output level per unit light receiving area.

On the slit plate 7, a window group 11 as one end side window group composed of _six windows Si _{1 to} Si ₆ is formed at a portion corresponding to the light receiving elements Di _{1 to} Di _6, and the light receiving element Dj ₁ at a site corresponding to the ～Dj _6, likewise, the window group 12 of the other end side window group of six windows Sj ₁ ~Sj ₆ is formed. Each of these six windows corresponds to the number of tracks T _{1 to} T ₆ within a range in which the pair of recording head W ₁ and reproducing head R ₁ of the combination head 3 can move. Windows Si ₁ ~ Si ₆・ Sj ₁ ~ Sj
_The slit plate 7 is configured to move together with the movement of the combination head 3 in the ± Y direction because the slit plate 7 is provided integrally with the combination head 3. Each of the windows Si _{1 to} Si ₆ and Sj _{1 to} Sj ₆ has a width e (e = e = e = e) in which the width in the Y direction can correspond to the waving of the magnetic tape 1.
100 μm) and the width in the X direction is the light receiving elements Di _{1 to} Di ₆
- it is set to appropriate width f from Dj ₁ ~Dj ₆ can obtain sufficient output. Windows Si _{1 to} Si ₆ and Sj _{1 to} Sj ₆ are windows Si ₁
Sj ₁ is provided on the + X direction end side and the −Y direction end side, and the windows Si _{1 to} Si ₆ and Sj _{1 to} Sj ₆ are respectively the same pitch d in the + Y direction as the track pitch of the magnetic tape 1. (D = 12
0 .mu.m) and are sequentially arranged in parallel in the -X direction at a pitch g. Further, the light receiving elements Di _{1 to} Di ₆ and the light receiving elements Dj _{1 to} Dj ₆ are arranged at positions displaced in the Y direction by 1/4 inch corresponding to the width of the magnetic tape 1. Further, in the present embodiment, when the recording head W ₁ and the reproducing head R ₁ of the combination head 3 are located at the track T ₁ position, the Y of the window Si ₁ · Sj ₁ is Y.
The center of the direction is set so as to be at the center position of each of the light receiving elements Di ₁ and Dj ₁ , that is, at the position corresponding to the ± Y direction edge of the magnetic tape 1.

The light receiving elements Di _{1 to} Di ₆ and Dj _{1 to} Dj ₆ are connected to a head driving means (not shown). The head drive means receives the light-receiving elements Di _{1 to} Di when the combination head 2 is moved to the relative positions of the recording heads W _{1 to} W ₈ and the reproducing heads R _{1 to} R ₈ and the tracks T _{1 to} T _{48. 6} , the combination head 3 is driven in the ± Y direction of the magnetic tape 1 by feedback control so that the difference between the outputs of the pair of light receiving elements corresponding to the light receiving elements Dj _{1 to} Dj ₆ becomes zero. The relative position between 1 and the combination head 3 is maintained at a predetermined fixed position.

Further, as shown in FIG. 5 (a), a sufficient amount of light is provided at each of the ± Y direction end portions of the magnetic tape 1 and the portions facing the above-mentioned light receiving element groups 9 and 10 via the slit plate 7. Light emitting means 8 capable of irradiating the light of 9
8 are provided.

In the above configuration, for example, in the reproducing operation of the magnetic recording / reproducing apparatus, when reproducing all the tracks T _{1 to} T ₄₈ including the tracks T ₁ , T ₁₃ , T _25, and T ₃₇ , the combination head 3 Driven by the head driving means, the reproducing head R ₁ and the track T ₁ , the reproducing head R ₃ and the track T ₁₃ ,
Playhead R ₅ and track T ₂₅ , Playhead R ₇ and track T
₃₇ and ₃₇ move to relative positions with respect to the corresponding magnetic tape 1. At this time, the head driving means, by feedback control, the light receiving element by the incident light from the light emitting means 8 and 8 through the window Si ₁ and window Sj ₁ of the slit plate 7 and the end portions of the magnetic tape 1 in the ± Y direction. The output difference between Di ₁ and the light receiving element Dj ₁ is calculated, and the combination head 3 is driven so that this output difference becomes zero. Therefore, the combination head 3 moves following the waving of the magnetic tape 1, and the relative position between the two is held at an accurate position. In this state, when the magnetic tape 1 is run in the X direction, the reproducing head
The tracks T ₁ , T ₁₃ , T ₂₅ , T ₃₇ are reproduced by R ₁ , R ₃ , R _5, and R _7, and when the magnetic tape 1 is run in the −X direction,
Tracks T ₇ , T ₁₉ , T ₃₁ by playback heads R ₂ , R ₄ , R ₆ , R ₈
Playback of · T ₄₃ is performed.

When one round-trip playback is completed in this way, the same goes for tracks T ₂ , T ₁₄ , T ₂₆ , T ₃₈ and tracks T ₈ , T _20.
・ When reproducing T ₃₂ and T _44, the light receiving element by the incident light through the window Si ₂ and the window Sj ₂ and the end of the magnetic tape 1 in the ± Y direction.
Di ₂ / Dj ₂ output difference, window Si ₃ / window Sj during playback of tracks T ₃ , T ₁₅ , T ₂₇ , T ₃₉ and tracks T ₉ , T ₂₁ , T ₃₃ , T _45
3 and the output difference of the light receiving element Di ₃ · Dj ₃ due to incident light through the ± Y direction end side of the magnetic tape 1, tracks T ₄ · T ₁₆
・ When reproducing T ₂₈・ T ₄₀ and tracks T ₁₀ , T ₂₂ , T ₃₄ , T ₄₆ , the light receiving element by the incident light through the window Si ₄ , the window Sj ₄ and the end of the magnetic tape 1 in the ± Y direction. Di ₄ / Dj ₄ output difference,
Trucks T ₅ , T ₁₇ , T ₂₉ , T ₄₁ and trucks T ₁₁ , T ₂₃ , T
_When reproducing ₃₅ / T _47, the light receiving element Di by the incident light through the window Si ₅ / window Sj ₅ and the end of the magnetic tape 1 in the ± Y direction
Output difference of ₅ / Dj ₅ , window Si ₆ , window Sj ₆ during playback of tracks T ₆ , T ₁₈ , T ₃₀ , T ₄₂ and tracks T ₁₂ , T ₂₄ , T ₃₆ , T ₄₈
And by moving the combination head 3 so that the output difference of the light receiving elements Di ₆ and Dj ₆ due to the incident light through the ± Y direction end portions of the magnetic tape 1 becomes zero, the track switching operation and The track following operation is performed, and the reproduction for all the tracks T _{1 to} T ₄₈ is completed. The above operation is the same in the recording operation.

As described above, in this embodiment, since the slit plate 7 moves integrally with the combination head 3, it is possible to reduce the weight of the moving portion as compared with the structure of the first embodiment.

Further, similar to the configuration of the first embodiment, stable position control can be performed without being affected by temperature.

〔The invention's effect〕

As described above, the tracking control device for the magnetic recording / reproducing apparatus according to the first aspect of the present invention includes a combination head having a number of magnetic heads smaller than the number of tracks of the magnetic tape, and a plurality of tracks including the combination head. Head drive means for moving the magnetic tape in the width direction of the magnetic tape formed in parallel to the tape running direction, and a plurality of track switching operations by moving the combination head by the head drive means for all tracks. In the magnetic recording / reproducing apparatus for performing recording / reproducing as described above, the combination head is provided with as many light-receiving elements as the number of tracks of a magnetic tape corresponding to a predetermined magnetic head of the combination head, at one end side in the tape width direction. And the other end side, and the one end side light receiving element The light receiving elements of the group and the light receiving elements of the other end side light receiving element group are arranged side by side in the tape width direction so as to have a corresponding relationship with each other. The light receiving element of the one end side light receiving element group and the other end side light receiving element group have a correspondence relationship with the track and correspond to this track when the magnetic head moves to an arbitrary track position. Are provided so that the outputs of the pair of light receiving elements have a fixed relationship, and a light emitting means is provided at a position facing the light receiving element via both end sides in the width direction of the magnetic tape, and the head driving means, When the magnetic head of the combination head is moved to a predetermined track position, the output of a pair of light receiving elements corresponding to the predetermined track is generated by the incident light from the light emitting means through both ends in the tape width direction. So as to satisfy the predetermined relationship, it has a configuration for performing feedback control.

Therefore, with a low-cost configuration, and without being affected by variations in the relative position detection output due to temperature changes,
It is possible to detect each relative position of the magnetic tape and the combination head with high accuracy, and it is possible to perform highly accurate tracking control. Therefore, it is possible to achieve high-accuracy and large-capacity magnetic recording / reproducing.

As described above, the tracking control device of the magnetic recording / reproducing apparatus according to the second aspect of the present invention includes a combination head having a number of magnetic heads smaller than the number of tracks of the magnetic tape, and a plurality of tracks including the combination head. Head drive means for moving the magnetic tape in the width direction of the magnetic tape formed in parallel to the tape running direction, and a plurality of track switching operations by moving the combination head by the head drive means for all tracks. In the magnetic recording / reproducing apparatus for recording / reproducing all of the information, the combination head is integrally provided with a slit plate, and the slit plate has the same number of tracks as a magnetic tape corresponding to a predetermined magnetic head of the combination head. The number of windows is different from the one end side in the tape width direction Formed on the side of the slit plate, and on the side opposite to the side of the magnetic tape in the slit plate, the above-mentioned windows and the light receiving elements individually corresponding thereto are separately fixed to the combination head, and the one end side of the slit plate is formed. The windows of the window group and the windows of the other end side window group are arranged in parallel in the tape width direction so as to have a corresponding relationship with each other, and each of the corresponding pair of windows corresponds to a predetermined track of the magnetic tape. The window of the one end side window group and the window of the other end side window group that have a correspondence relationship are a pair of windows and a tape width corresponding to the track when the magnetic head moves to an arbitrary track position. Are provided so that the outputs of the light receiving elements due to the light incident through both end sides in the direction have a constant relationship, and are located at the positions facing the light receiving elements through the both end sides in the width direction of the magnetic tape and the slit plate. Is equipped with a light emitting means, Means, when the magnetic head of the combination head is moved to a predetermined track position, by the incident light from the light emitting means through a pair of windows corresponding to the predetermined track and both end sides in the tape width direction, The feedback control is performed so that the outputs of the light receiving elements corresponding to the both windows described above satisfy a certain relationship.

Therefore, it is possible to obtain the same effect as that of the structure of claim 1, and the structure in which the combination head and the slit plate move integrally makes it possible to move the moving part as compared with the structure of claim 1. It is possible to realize high-accuracy and large-capacity magnetic recording / reproducing with reduced weight.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a front view showing the positional relationship among a magnetic tape, a combination head and a light receiving element. FIG. 2A is a schematic plan view showing the positional relationship between the magnetic tape, the combination head and the light receiving element holding member. FIG. 2 (b) is the same front. FIG. 3 is a schematic front view of a magnetic tape and a combination head used for explaining the recording and reproducing system of the magnetic recording / reproducing apparatus. 4 to 5 show another embodiment of the present invention. FIG. 4 is a front view showing the positional relationship among the magnetic tape, the combination head, the light receiving element, and the windows formed in the slit plate. FIG. 5A is a schematic plan view showing the positional relationship among the magnetic tape, the combination head, the light receiving element holding member, and the slit plate. FIG. 5 (b) is the same front. 1 is a magnetic tape, 2 is a track group, 3 is a combination head, 4 is a light receiving element holding member, 5 is a light receiving element group (one end side light receiving element group), and 6 is a light receiving element group (other end side light receiving element group) , 7 is a slit plate, 8 is a light emitting means, 11 is a window group (one end side window group), 12 is a window group (other end side window group), Da _{1 to} Da ₆
Db _{1 to} Db ₆・ Di _{1 to} Di ₆・ Dj _{1 to} Dj ₆ are light receiving elements, Si _{1 to} Si ₆・
Sj _{1 to} Sj ₆ are windows, T _{1 to} T ₄₈ are tracks, W _{1 to} W ₈ are recording heads, and R _{1 to} R ₈ are reproducing heads.

Claims (2)

[Claims] 1. A combination head having a smaller number of magnetic heads than the number of tracks on the magnetic tape, and the combination head is moved in the width direction of a magnetic tape having a plurality of tracks formed in parallel to the tape running direction. A magnetic recording / reproducing apparatus for recording or reproducing on all tracks by a plurality of times of track switching operations by moving the combination head by the head driving means, the combination head comprising: , A number of light-receiving elements equal to the number of tracks of the magnetic tape corresponding to a predetermined magnetic head of the combination head are provided on one end side and the other end side in the tape width direction, and the one-end side light-receiving element group receives light. There is a corresponding relationship between the element and the light receiving element in the other end side light receiving element group. Are arranged in parallel in the tape width direction, and each of the corresponding pair of light receiving elements has a corresponding relationship with a predetermined track of the magnetic tape, and the light receiving elements of the one end side light receiving element group and the other end side The light receiving element of the light receiving element group is provided so that when the magnetic head moves to an arbitrary track position, the outputs of the pair of light receiving elements corresponding to this track have a constant relationship, and A light emitting means is provided at a position facing the light receiving element via both end sides of the head drive means, and the head drive means, when the magnetic head of the combination head is moved to a predetermined track position, both end sides in the tape width direction. The feedback control is performed so that the output of the pair of light receiving elements corresponding to the predetermined track satisfies a certain relationship by the incident light from the light emitting means via Tracking control apparatus of a magnetic recording and reproducing apparatus characterized. 2. A combination head having a smaller number of magnetic heads than the number of tracks on the magnetic tape, and the combination head is moved in the width direction of a magnetic tape having a plurality of tracks formed in parallel to the tape running direction. A magnetic recording / reproducing apparatus for recording or reproducing on all tracks by a plurality of times of track switching operations by moving the combination head by the head driving means, the combination head comprising: A slit plate is integrally provided, and the slit plate has windows as many as the number of tracks of the magnetic tape corresponding to the predetermined magnetic head of the combination head on one end side and the other end side in the tape width direction. Formed on the side opposite to the magnetic tape side of the slit plate, Each of the windows and the corresponding light receiving element are fixed separately from the combination head, and the above-mentioned one end side window group windows and the other end side window group windows in the slit plate correspond to each other individually. Are arranged side by side in the tape width direction, and each of the corresponding pair of windows has a corresponding relationship with a predetermined track of the magnetic tape, and the one end side window group window and the other end side window. The group window means that when the magnetic head moves to an arbitrary track position, a pair of windows corresponding to the track and the output of the light receiving element by the light incident through both end sides in the tape width direction are constant. Are provided so as to have a relationship with each other, and a light emitting means is provided at both ends in the width direction of the magnetic tape and a position facing the light receiving element via the slit plate, and the head driving means drives the magnetic head of the combination head to a predetermined position. Move to track position At this time, due to the incident light from the light emitting means through the pair of windows corresponding to the predetermined track and the both end sides in the tape width direction, the outputs of the light receiving elements corresponding to the both windows are constant. A tracking control device for a magnetic recording / reproducing device, which performs feedback control so as to satisfy the relationship.